Hydrogen peroxide (H₂O₂)-mediated receptor signaling (Redox Signaling)

• In the normal physiology, the activation of various receptors triggers the production of intracellular hydrogen peroxide (H₂O₂), which acts as a second messenger such as calcium or cyclic adenosine monophosphate (cAMP). H₂O₂ induces the oxidation of cysteine thiol on target proteins. Such oxidation causes conformation change and affects protein-protein interaction and activity. After the signal,  H₂O₂ is eliminated by Prx enzymes through this coupling reaction.

  In a diseased state such as inflammation or a stress condition, however, high H₂O₂ levels causes Prx enzyme inactivation and the overoxidation of target proteins and macromolecules. Consequently, such abnormal overoxidation causes tissue hyperplasia, dysfuction and damage. If we could replace the inactive Prx enzymes with stable chemical agents, we could control abnormal H₂O₂ levels and thus normalize cellular function. Our drug development starts with this new redox signaling.